Table of Contents - SEN 2216

Use of electronic altimeters in the Rhône-Alpes World Cup fly off
(from FB posted by Allard van Wallene - graphs shown on FB not shown)

The Dutch Free Flight Subcommittee filed a proposal with the CIAM to allow the
use of altimeters in fly offs in case a sportsman would contest the flight time as
recorded by the timekeepers. The contest organizers of the Rhône-Alpes World
Cup agreed on testing the use of electronic altimeters during the fly off. To avoid
handing- in of pre-recorded altimeter data, the contest director would instruct
all flyers to lift and lower their models overhead and lower it to ground level in a
pre-defined sequence to let each altimeter record an unique ‘signature’. Only
graphs with this signature would be considered valid. A total of five contestants
had altimeters in their ships and a few minutes prior to the fly off, van Wallene
instructed them to perform the motions to create the signature. It was
interesting to see that also contestants without altimeters joined the show. Three
were using the ‘Hobbyking / Fly Dream’ altimeter (van Dijk, Maassen, van
Wallene), one the stock M&K altimeter (Reuss) and one the Aberlenc system
(Aberlenc). Noteworthy is that the two last systems do not record altitudes prior
to the launch, so both towing sequence as well as the unique signature were not
recorded, which would render their results invalid. All flights were timed by
experienced timekeepers and all models could be seen to the ground provided
they were equipped with LED flashers. All altimeter graphs were sent to van
Wallene for further analysis and they are presented below:

Reuss’ flight:
As already indicated above, the M&K altimeter system does not record any data
prior to the launch of the model. No signature is recorded. Furthermore, the rule
proposal stipulates, that the altitude recording frequency should be at least two
per second. The M&K records 1 altitude per 5 seconds, so also here this system
would not comply with the rule proposal. Nevertheless, that altitude data show
interesting information of the flight. Its publication parallel to a result lists
would give very interesting information in addition to the flown time.
Notes: launch altitude 88m, landing altitude is below start level, model landed in
a tree. Thermal activity during first 2 minutes, relatively steady descent after,
recording resolution (1 per 5 seconds) insufficient to establish correct flight
time, both unique signature and towing sequence not recorded. Rough flight time
estimate from graph 8 min, 10 sec. , time as recorded by time keeper 8 min, 10
sec. No grounds for dispute but graph considered invalid as not compliant with
recording resolution and absence of unique signature.

Aberlenc’s flight:
Notes: launch altitude 88m, landing altitude is below start level, sink during first
minute, thermal activity after for 1.5 minutes, relatively steady descent after,
recording resolution unknown, possibly lack of possibility to zoom-in to the
landing part gives insufficient information to establish correct flight time, both
unique signature and towing sequence not recorded. Rough flight time estimate
from graph 7 min, 10 sec. , time as recorded by time keeper 7 min, 15 sec. No
grounds for dispute but graph considered invalid as not compliant due to lack of
unique signature.

Van Dijk’s flight:
Flight overview:
The unique signature can be seen around the 8 min. mark. Noteworthy is the
failed attempt between 11 and 12 minutes due to a line cross as reported above.
Launch was 93 meters.
Flight details:
Altimeter data show a flight time of 5 min. 51 sec. The timekeeper recorded 5
min. 37 sec., a difference of 14 seconds. Van Dijk did not use a LED flasher on his
model, which went out of sight against the dark background which contributed
to the failing 14 seconds.
Maassen’s flight:
Notes: launch altitude 64m, landing altitude is below start level, lift during first
minute, relatively steady descent after, recording resolution 8/second, both
unique signature and towing sequence recorded. Unique signature can be seen
right of 10 minute mark. No grounds for dispute. Although the unique signature
is shown, Mr. Maassen had set the recording resolution of his altimeter to 1/sec.
(his altimeter can be set to up to 8/sec.). The recording resolution was therefore
not compliant and the graph therefore invalid.
Zooming –in on relevant parts of flight shows unique signature, start and end of
flight.
Signature:
The unique signature as instructed to the fly off participants was: lift, hold for 9
seconds, lower to ground, hold for 9 seconds, lift, hold for 7 seconds.
Flight time:
Flight time as shown on graph is 3 min., 27 sec. Recorded by time keepers 3 min,
15 sec. Also Maassen did not use LED strobe flashers which explains the shorter
time recorded by the time keepers, as the models disappeared from view against
a dark background.

Van Wallene’s flight:
Note: as van Wallene instructed the participants to record the unique signature,
an additional ‘lift overhead’ is recorded prior to the ‘official’ signature as a
demonstration to the participants.
Flight and signature:
Signature (note ‘test’ prior to the two lifts):
Flight time:
Notes: launch altitude 113m, landing altitude is below start level, lift during first
1.5 minute, relatively fast descent after, recording resolution 8/second, both
unique signature and towing sequence recorded. Unique signature can be seen
between 7 and 8 minute mark. No grounds for dispute. Both unique signature is
shown recording resolution of altimeter 8/sec. Graph therefore valid.
Zooming –in on relevant parts of flight, shows unique signature, start and end of
flight. Time keeper recorded 5 minutes, real flight time 5 min. and 9 sec. The 9
second difference was caused by the fact that the model disappeared behind an
elevation in the field.

Conclusion:
Electronic altimeters can be used to accurately determine the real flight time,
provided the altimeter complies with the requirements as defined in the rule
proposal. During the test run, only the Hobbyking altimeter provided useful data
provided the recording resolution is set at 4 or 8 measurements per second. The
recorded unique signature is recorded in the data and shown in the graphs to
prevent the use of pre-recorded data. The use of LED flashers have a substantial
effect on the time as recorded by the time keepers, in particular when the model
is gliding against a dark background (e.g. hill or trees

FB Comments

Frank Adametz DANKE. SEHR Interessant.

Bernard Guest Excellent test Allard. Certainly gives a positive indication that further testing should be done in the coming year.

Chris Edge Many thanks for organising the test and sharing the results Allard. My perspective is this: From the limited data and for the flights types* shown then altimeters gave a 'correct' in-flight time (with a small tolerance) for ALL the flights. By 'flight types' I mean a flight with a definite and positive vertical launch and a positive termination (stop). The big problem is where you don't have either of those two situations (ie a poor launch or a unclear stop) as automatically the altimeter data would be invalid. It also doesn't stop someone giving their altimeter to someone else and claiming a max to help, say, a team result. Given this was a test and everyone knew what was expected, it's disappointing that only 2 out of 5 people followed the draft rules correctly, so in the heat of a contest how would you propose to get flyers to do things better such that their data was admissible ? CHE

Allard van Wallene
Allard van Wallene Chris,
-The proposal is not an official rule and developers of FF electronics will only move when there is a need to do so (rule becoming effective).
-The test was announced on Facebook, there are sportsmen who are not on Facebook (yes hard to believe but a fact, e.g. Kosh and Kog)
-Like with all new rules, there will be some sportsmen who are unaware of changes. Some are even unaware of old rules (e.g. practice flying upwind of starting line to name one).
-I do not see any reason why a sportsman would give his altimeter result to a fellow competitor in a fly off. If for a team mate, it would not make a difference for the final team standings. If one altimeter result is used for more than 1 flyer, this will be immediately evident as no two altimeter graphs are the same -> disqualification of the 2 sportsmen. Of course there is a possibility where one sportsman maxes and gets the max without dispute. He hands over the altimeter to a fellow competitor who did not max but does file a dispute. One way out of this is to record the start of towing and the start of the launch. The altimeter graph must show these two times. For two contestants to start towing and launch simultaneously is impossible in my opinion.
-A float off line launch (is it at all possible with bunters?) is a very unlikely scenario. Would a launch at 50 meters be even competitive compared to a 100m+ launch to have a dramatic effect on the final results? Also unlikely. An inconclusive landing is a possibility and in such a case the time keeper's time counts. In any case, if the model lands after a period of zero sink, the time where the model stops sinking will be designated as 'landing' in the graph which is de facto shorter than the flown time. So no flights longer than the time keeper's recording are at all possible, only shorter ones.
-Finally one remark: the proposal was drafted to avoid unfair outcome where the true performance of a model is not properly registered by the time keepers. It was never intended to reduce cheating. Cheating can be done in so many different ways. Using this as an argument against a proposal is a weak argument in my opinion.
Like · Reply · 12 mins · Edited

F1E and Golf Scoring

From: Aram Schlosberg

F1E normalizes raw time scores, awarding those who have maxed or have the highest score each round with a shining 100.00. But when the difference is one second, the conversion requires a lot of attention to the normalized score’s fraction (98.XX). Although the normalization is correct mathematically, a hand calculator is always needed.

Golf uses another scoring paradigm: The leader is designated by a 0, and those with more strokes are designated by the number of strokes they are behind. So, if three players are a stroke behind, their score are (minus) 1 and if the next player is three strokes behind the leader their score is (minus) 3 and so on.

Applying this scoring system to F1E, suppose the highest time was say 4:00 (four minutes), then the leader would get a score of zero. The flier with 3:59 would get (minus) 1 and the one with 3:00 would get (minus) 60 for that round.

A variant is to subtract the score from the nominal round’s max. So it the nominal max was 5:00, the first flier would get (minus) 60, the second (minus) 61 and the third (minus) 120. And if a flier misses a round, they would be awarded (minus) 240 or (minus) 300 respectively. In either case, a flier’s final score is the sum of their individual round scores. The lowest score (that could be 0) wins.

So, negative integers (seconds) replace real number fractions. Scoring could even be done using a pencil.

Aram

A reserve day? What's the issue?

From: Michael Woodhouse

The organiser decides a programme. A reserve day is a reasonable option to include. The competitor can decide to enter or not under the terms provided for the event. The organiser then operates these terms.

Simple? If you book the trip home on the reserve day its your choice. The contest is flown on that day then tough. You should plan things better.

Michael Woodhouse

Arizona Champs in December

On December 3 and 4 the Arizona Free Flight Championships will be held in Eloy, Arizona. This is the last America’s Cup and National Cup contest West of the Mississippi for the year 2016. There are FAI, AMA, NFFS and SAM, and events. On the desert flying field in Eloy it will be cool in the mornings but should warm up to about 70° during the day. The 2, FAI and AMA, fliers can be downloaded from the NFFS web site, click on the “Arizona Championships” in the Master Contest Calendar.

For information on the 3-day 2017 Southwest Regional Model Airplane Championships on January 14-16 go to aalmps.com/16info.htm which will be current soon – please use the Entry Forms to pre-enter before Jan. 1, 2017. This will be the 69th SWR.

Please fly with us in Eloy!

Peter Brocks

Another Rule

From:Dave Mayer

Well Bob Parker finally got it right with his three rules! I even make it
even simple by my S H Factor! S--t Happens! Always another contest, have
fun, and be sure to ..."Laff A Little!"

Cordially and respectfully yours,

Dave Mayer
P.S.
I don't know if anyone remember me? I was the ...*mysterious flyer *at the
National Championship contest many years ago at Lost Hill who showed up my
son, Steve, and his red tail hawk. I even won a 3rd place in a free flight
rubber event.. Still have a few models, and might just show up again with
one of my Great, great, grandsons! Currently utilizing my many skills
that I have learned thru building model airplanes with my current venture
into ..."Sport Safety Technology!" * www.csr-sst.com/
<http://www.csr-sst.com/>* You can just click on the web address here
and you will find me!